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排序方式: 共有527条查询结果,搜索用时 31 毫秒
41.
Valerie L. Flax Chrissie Thakwalakwa John Phuka Ulla Ashorn Yin Bun Cheung Kenneth Maleta Per Ashorn 《Appetite》2009,53(2):195-202
The efficacy of lipid-based nutrient supplements (LNS) versus corn–soy blend (CSB) in promoting the growth of moderately malnourished children is currently being tested, but information about maternal attitudes towards the two supplements is lacking. This research studied 504 Malawian mothers’ attitudes about LNS and CSB through exit interviews completed at the end of three 12-week clinical trials and compared differences between the groups. Exploratory analyses of factors associated with withholding of supplements during fever, diarrhea, and cough were performed using logistic regression. Mothers generally had similar, positive attitudes towards LNS and CSB. Both supplements were said to be highly acceptable, children learned to eat them within two weeks, and mothers were willing to use them again. Mothers in the LNS group were reportedly more likely to withhold supplements from their children during cough, due to its sweetness, and were willing to pay more for a one-week supply of supplement than mothers in the CSB group. Maternal literacy was negatively and child's weight-for-height z-score was positively associated with withholding of supplements during illness. Our results indicate that the sweetness in LNS should be reduced, and programs using supplements in Malawi could include advice on appropriate feeding of supplements during illness. 相似文献
42.
43.
目的 研究处方中的辅料及工艺对瑞舒伐他汀钙片混合均匀度及含量均匀度的影响。方法 采用粉末直接压片工艺,通过单因素试验,考察处方中乳糖的型号、微晶纤维素的型号、乳糖与微晶纤维素的比例、钙盐的种类及交联聚维酮用量对混合均匀度及含量均匀度的影响;同时研究混合工艺对混合均匀度及压片工艺对含量均匀度的影响。结果 不同的乳糖型号(T80、PW80、315)、微晶纤维素型号(PH102、M102、102)、乳糖与微晶纤维素的比例(1:1、3:1、1:3)、钙盐的种类(磷酸钙(细颗粒)、无水磷酸氢钙(细颗粒、细粉)、碳酸钙(细粉))的处方混合均匀度及含量均匀度良好,磷酸钙(粗颗粒)的处方混合均匀度及含量均匀度较差。在混合容器中加入50%的乳糖,之后加入原料药、微晶纤维素、交联聚维酮和磷酸钙,以10 r·min-1混合20~25 min;再加入剩余的乳糖,以10 r·min-1混合15~25 min,物料混合均匀度良好。重力加料器及压片速度(10~20 r·min-1)的含量均匀度良好;强制加料器及压片速度(30 r·min-1)的含量均匀度较差。结论:通过研究筛选出了适合粉末直压工艺的乳糖型号、微晶纤维素型号、乳糖与微晶纤维素比例、钙盐种类及交联聚维酮用量。考察了混合工艺参数范围,优选了重力加料器及压片速度(10~20 r·min-1),获得了良好的混合均匀度和含量均匀度。 相似文献
44.
Efficiency of split-mouth designs 总被引:1,自引:0,他引:1
The purpose of this paper is (1) to investigate the similarity of the amount, distribution, and severity of periodontal disease of the within-patient experimental units, (2) to estimate the relative efficiencies of split-mouth designs when compared to whole-mouth designs, and (3) to discuss how stratification on initial pocket depth can result in large differences in the power of the test-statistics in the different disease categories. Periodontal disease characteristics are not always homogeneously distributed over the within-patient experimental units and this heterogeneity can reduce the efficiency of split-mouth designs. In particular, if analyses are stratified on initial pocket depth, sites with an initial probing depth deeper than 6 mm may be small in number and asymmetrically distributed when compared to sites with an initial probing depth less than 6 mm. This may result in large differences of the power of the test statistics among the different disease categories and should lead to a careful interpretation of the statistical significance tests. When disease characteristics are symmetrically distributed over the within-patient experimental units and a sufficient number of sites is present per experimental unit, the split-mouth design can provide moderate to large gains in relative efficiency. In the absence of a symmetric disease distribution, whole-mouth clinical trials may be preferable. 相似文献
45.
主动脉瓣狭窄下游流场均匀性研究 总被引:1,自引:0,他引:1
目的 :通过研究主动脉瓣 (AV)狭窄下游流场均匀性指标 ,探讨按照常规分类标准程度分类不同的患者流场均匀性之间的差异 ,探讨该指标对AV狭窄程度分类的意义 ,以及对AV狭窄患者手术时机选择的临床价值。 方法 :对 33例不同程度的AV狭窄患者 ,采用多普勒超声诊断仪于左室长轴及心尖五腔切面分别测定各点的峰值血流速度 ,并且计算各切面的最大速度差值 (△Vmax)作为流场均匀性指标 ,并且与主动脉瓣口面积进行统计分析比较。 结果 :不同程度AV狭窄之间流场均匀性存在显著差异 (P <0 .0 1)。 结论 :①流场均匀性指标简单、易行、重复性好 ,可作为AV狭窄患者的临床随访指标 ;②该指标对AV狭窄程度的分类有重要的参考价值 ;③该指标对AV狭窄患者手术时机的选择有重要的临床价值。 相似文献
46.
综合我科6年来APEX HELIX双探头SPECT的质控结果.对该系统的固有均匀性和固有能量分辨率两个质控指标进行统计分析.评估系统性能。统计分析结果表明.系统的两个探头校正后的两种质控指标较校正前都有显著性改善.提示系统校正性能良好:同时.通过系统质控校正后的均匀性和能峰.两个探头之间无显著性差异,提示系统双探头匹配良好。系统在一个较长时期内.工作性能稳定、设备运行良好.满足临床使用要求。 相似文献
47.
盐酸氟奋乃静片含量均匀度的流动注射分析 总被引:2,自引:0,他引:2
基于盐酸氟奋乃静在一定pH值下与氯化钯反应,生成红色配位产物,于485nm处出现最大吸收,可籍以测定含量。线性范围0 ̄80μg/ml,RSD约为1%。 相似文献
48.
以过氧化二异丙苯(DCP)为引发剂,甲基丙烯酸缩水甘油酯(GMA)为活性单体,高抗冲苯乙烯(HIPS)通过熔融接枝制得了动能化的高抗冲聚苯乙烯接枝物(HIPS-g-GMA)。用红外光谱和电子能谱对其结构进行了表征。HIPS-g-GMA的红外谱图,证明GMA已经接枝到HIPS上。电子能谱分析也提供了相似的结论。研究了单体浓度和DCP用量对产物接枝率的影响,并用化学滴定方法测定了接枝物的接枝率。用DSC、SEM、WAXD、DMA等研究了PBT/HIPS和PBT、HIPS-g-GMA的结晶、形态结构、动态力学性能及力学性能随组成的变化。SEM及DMA分析表明增容后体系的相容性得到改善,力学性能有较大提高。 相似文献
49.
Chi Wang Young‐Da Fan Chung‐Chiu Chen Chung‐Hau Hung 《Macromolecular chemistry and physics.》2007,208(22):2428-2438
Crystalline/amorphous binary mixtures of polystyrene with different tacticities, syndiotactic/atactic isomers (sPS/aPS), have been systematically studied to reveal the composition dependence of the blend morphologies, i.e., sPS lamellar structure and aPS diluent segregation, developed after isothermal crystallization. To reveal the molecular weight effect of the aPS diluents, four different of aPS were used to prepare blends with various compositions. After being melt crystallized isothermally at 250 °C, all blends were investigated by means of POM, WAXS, and SAXS as well as SEM and TEM to reveal the spherulitic and lamellar morphologies developed.
50.
《Macromolecular chemistry and physics.》2017,218(13)
The self‐assembly and structure formation in binary blends of asymmetric polystyrene‐block‐poly(4‐vinylpyridine) diblock copolymers in different solvent systems and the bulk morphology of the blend films are studied by using dynamic light scattering, small‐angle X‐ray scattering, and transmission electron microscopy. In dilute solutions, the chains of pure diblock copolymers or binary blends of diblock copolymers having similar or different molecular weights remain as unimers, form common micelles in selective solvents or form unimers in coexistence with micelles in slightly selective solvents or solvent mixtures. The blends show mixing of the chemically similar blocks in the blend films and solutions at high concentrations. A single‐phase with common spherical morphology is formed in the blend films similar with the morphology of the individual components in the pure state. The characteristic length scale of the blends depends on the number average molecular weight following the typical scaling behavior of a strongly segregated block copolymer.